Flower-Like BiOI Microspheres Decorated with Plasmonic Gold Nanoparticles for Dual Detoxification of Organic and Inorganic Water Pollutants

Abstract

The development of bismuth-based photocatalysts in response to emerging demand for solving environmental problems has attracted immense interest over the past few years. This is owed to their low cost, nontoxicity, and high stability. Here, we report the synthesis of a nanohybrid consisting of 3D flower-like BiOI microspheres decorated with plasmonic gold nanoparticles (∼15 nm) to experience enhanced photocatalytic activity. Various characterization tools such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) have been used to investigate the morphology and crystallinity of the photocatalyst. The formation of the nanohybrid by the gold nanoparticles and BiOI microspheres has been confirmed by Raman as well as picosecond resolved ultrafast spectroscopy. The as-synthesized nanohybrid exhibits a superior photocatalytic activity toward the detoxification of organic (methyl orange) as well as inorganic (hexavalent chromium) water pollutants under visible and red light (λ > 600 nm) irradiation. Our detailed ultrafast spectroscopic studies link the enhanced photocatalytic activity of the nanohybrid to an improved charge carrier separation in the metal−semiconductor interface. In addition, we find that the degradation process of the dye and the reduction of hexavalent chromium [Cr(VI)] are based on two completely different mechanisms. Moreover, our synthesized nanohybrid efficiently retains its activity as well as its structural stability after several cycles of light irradiation, which highlights it as a promising candidate for environmental remediation.

Bi‐based photocatalysts for light‐driven environmental and energy applications: Structural tuning, reaction mechanisms, and challenges

“…The BiVO 4 (040)/Ag 2 O heterostructures owns the excellent capability in light absorption and the efficient charge separation, which enhanced the photocatalytic methylene blue (MB) degradation activity and O 2 evolution in Figure 11B, 206 Chatterjee et al synthesized a 3D flower‐like BiOI microspheres with plasmonic Au nanoparticle decoration, which shows an outstanding photocatalytic detoxification for organic (methyl orange) as well as inorganic (hexavalent chromium) water pollutants (Figure 11C). 207 Yu et al simultaneously achieved I − doping and plasmonic Bi metal deposition in BiOIO 3 . And Bi/I − co‐decorated BiOIO 3 exhibits widely strong photo‐oxidizing performance toward multiple pharmaceutical and industrial contaminant decomposition, including tetracycline hydrochloride, dye model Rhodamine (RhB), bisphenol A (BPA), 2,4‐Dichlorophenol (2,4‐DCP), phenol (Figure 11D).…”

“…Source : B, Reproduced with permission: Copyright 2019, Elsevier 206 . Source : C, Reproduced with permission: Copyright 2020, American Chemical Society 207 . Source : D, Reproduced with permission: Copyright 2015, American Chemical Society 208 …”

Boron‐doped Carbon Dots with Surface Oxygen Functional Groups as a Highly Sensitive and Label‐free Photoluminescence Probe for the Enhanced Detection of Mg2+ Ions

“…[39,41] Time-resolved PL (TRPL) results can support the CHEP further and here, we have recorded TRPL measurements for DS-BC10 with and without Mg 2 + ions. [57][58][59][60][61][62][63] As shown in Figure 5c and d, PL decay curves are non-linear on a logarithmic scale and PL counts increased after the addition of Mg 2 + ions. These results suggest that both radiative & nonradiative recombination rates are changed.…”

Dual Sensitization via Electron and Energy Harvesting in a Nanohybrid for Improvement of Therapeutic Efficacy

“…The positions (2θ value) of the diffraction peaks of Au NPs are observed to be at 38.13, 44.28, and 64.55°, which signify the (111), (200), and (220) crystal planes, respectively. 40 The absorption spectra (Figure 2a) of Rf in ethanol exhibit two characteristic peaks at 351 and 445 nm. In the case of Rf− ZnO and Rf−ZnO−Au, the change in the absorbance peak at 445 nm indicates the complex formation between Rf and the surfaces of both ZnO and Au−ZnO, as shown in Figure 2a.…”